This brisk first-person account by a Navy SEAL is an important historical work, though it, like the mission itself, is not flawless.

No Easy DayThe Firsthand Account of the Mission that Killed Osama bin Laden

Mark Owen with Kevin MaurerDutton: 315 pp., $26.95

Former Navy SEAL Matt Bissonnette did not put the first slug into Osama bin Laden when SEALs raided the terrorist's lair in Pakistan last year in May.

But he fired follow-up shots quickly and without remorse, as he describes in vivid, gruesome detail in "No Easy Day," written under the pseudonym Mark Owen with co-author Kevin Maurer:

"The point man's shots had entered the right side of his head. Blood and brains spilled out of the side of his skull. In his death throes, he was still twitching and convulsing," he writes. "Another assaulter and I trained our lasers on his chest and fired several rounds. The bullets tore into him, slamming his body into the floor until he was motionless."

Within minutes, the SEALs had identified the dead man as Bin Laden. A coded phrase was relayed to an admiral in Afghanistan, who flashed the news to a waiting President Obama: The mission to get Bin Laden, at long last, had been accomplished. Obama's gamble to green-light the assault, rather than an aerial bombing raid, had paid off.

Make no mistake: "No Easy Day" is an important historic document. Think if we had a first-person account of the last minutes of Hitler in his bunker or Yamamoto on his plane.

There will be other accounts of this mission, and maybe some will dispute key details of "No Easy Day." Anyone who has been in a traffic accident or witnessed a street crime knows that eyewitnesses can disagree sharply.

Still, "No Easy Day" is brisk and compelling in its telling of the training, execution and immediate aftermath of the Bin Laden mission by the elite Seal Team 6 — no easy task since the public already knows how it ended, with Bin Laden dead, no U.S. casualties and the Pakistanis furious that the U.S. had invaded their country.

On Tuesday, as the book went on sale, Pentagon press secretary George Little said officials have concluded it contains “sensitive and classified” material. And Rear Adm. Sean Pybus said it could provide insight into SEAL tactics that could put SEALs and their families at risk.

The Pentagon has threatened Bissonnette with legal action for supposedly breaking a secrecy agreement demanded of all SEALs. Whether that is a real threat or just institutional huff-and-puff remains to be seen.

Bissonnette has gone to lengths to avoid disclosing trade secrets about gathering intelligence and assaulting barricaded structures. And his first-name-only descriptions are so careful that you would not know one of the SEALs if he was standing next to you in the grocery store, although use of the word "dude," the phrase "the teams" and, of course, the F-word would be tipoffs.

Security aside, blandness is a problem. Couldn't the reader have been given at least some description of the SEAL who fired the shot as Bin Laden peeked out of his third-floor bedroom? Why did he fire at an unarmed subject? Did his fellow SEALs, known for hard-edge ribbing, give him a bad time later for possibly violating the order that the mission was not meant to be an assassination?

And what about pumping bullets into Bin Laden as he lay defenseless on the floor? Doesn't the Geneva Convention require the rendering of aid to even the most despicable of wounded combatants? Or do such rules not apply to U.S. special forces? Possibly to avoid such inconvenient questions, the White House insisted bin Laden was killed in a firefight.

"No Easy Day" gets its title from the SEAL motto about the grueling training for SEAL candidates at the base in Coronado: The Only Easy Day Was Yesterday. Bissonnette explains that he got hooked in junior high school on being a SEAL after reading the novel "Men in Green Faces" about SEALs in Vietnam, by former SEAL Gene Wentz and co-author B. Abell Jurus.

No surprise there. For all its cultural insistence on secrecy, there is a cottage industry of SEAL books. The founder of SEAL Team 6, Richard Marcinko, has had a second career writing SEAL pot-boilers. Indeed, no other similar-sized unit in the U.S. military has had as many books, documentaries and even Hollywood movies extolling its virtues.

With the additional subtitle of "The Autobiography of a Navy SEAL," Bissonnette's book says he grew up in Alaska and attended college in California (no names provided). He loved the physical challenge and the camaraderie of being a SEAL: That's a story well-known to any consumer of SEAL books or SEAL documentaries.

If Bissonnette has any special insight into the war in Afghanistan or the use of special forces against an insurgency, he has kept it to himself. There is some grousing about desk-bound officers and the politicians in Washington, but nothing you would not hear from the average enlisted rank.